Switch machine for railroads



Dec. 16, 1930. w. K. HOWE SWITCH MACHINE FOR RAILRQADS Filed Aug. 16,1929 Anow m l a tented Dec. 16, I936 fumrse' 'STA TESPATENT orificewnirirnor K. owe, or ROCHESTER, NEW YORK, ASSIGNOR TO GENERAL RAILWAYSIGNAL coMPANY, or noormsrna, NEW YORK SWITCH MACHINE roe RAILRQADSApplication filed August 16, 1929. Serial :No. 336,307.

This invention relates to power operated switch machines, and moreparticularly to means for safeguarding the manual manipulation orcranking of such switch machines.

It is desirable to provide a suitable crank, or equivalent manual means,by which the mechanism of a power operated switch matenance oradjustment; and it is also desirable to make provision so that the powermust be out off from the switch machine before the hand crank can beused. Such an arrangement is disclosed, for example, in my prior PatentNo. 1,466,903, dated'September 4, 1923. v V

In accordance with the present invention, it is proposed to provide anautomatic mechanical latch for the power cut-off device, so that whenthe'powercut-ofi' device has once been actuated to crank the machine byhand, this device is mechanically latched in this position, and can onlybe released to again permit the application of power to the machine, bysome authorized person, who has a key to unlock the mechanism cover.

The characteristic features, functions and advantages of the inventionwill be in part apparent, and in part pointed out as the description'progresses.

In the accompanying 7 drawing, Fig. 1 shows a fragmentary plan view ofan electrically operated switch machine of the type shown in my priorpatent. above mentioned; .Fig. 2 is a fragmentary transverse section online 22 of Fig. 1, through the mechanism casing, showing the cover; Fig.3 is a fragmentary section on line 3-3 of Fig. 1; Fig. 4 is afragmentary view ofthe guard plate for the crank socket, shown in 1tsoperated position to permit the insertlon of the crank; and Fig. 5 is afragmentary section on the line 55 of Fig. 4. In the specificconstruction of the electr1- cally operated switch machine, shown in myprior Patent 1,466,903, and to which this 1nvention has been shownapplied, the gearing between the electric motor for the switch machineand the throw bar connected to the switch points, includes a bevel gear5 and a shaft 6, provided with a socket 7 atthe upper end to receive asuitable hand crank, so that the gearing may be turned by hand. Toinsert this hand crank (not shown), ahinged cap 8, covering an openingin the mechanism cover 9, is raised, and a guard plate 10 is shiftedfrom the position shown in Fig. 1 to the position shown in Fig. 4, sothat the opening 10 in the guard plate 10 aligns with the crank socket7. The guard plate 10 is connected by a rod 11 to a contact 12, engaginga pair of insulated contact fingers 13, so that upon movement of theguard plate 10 said contacts are disengaged and the power circuit to theswitch machine is broken.

This guard plate 10 is pivoted at 14, and on one side of the pivot is arecess 15 (see Fig. 8) to receive a spring pressed plunger 16, set in ahole in the cross brace 17 When the guardplate 10 is in the normalposition shown in Fig. 1, partly covering the crank socket andcompleting the power circuit, the s'pring'plunger 16 engages in therecess 15 and holds the guard plate in this position, the upper end ofsaid plunger 16 and said re- Cess 15 being shaped to retain the guardplate in this normal position against jar and vibra tion, but permittingmanual shifting of the guard plate.

On the opposite side of the pivot 14 for the guard plate 10 is a hole20, as shown in Fig. 5, adapted to receive the end of another springpressed plunger 21 set in the cross brace 17. This otherspring pressedplunger 21 engages the hole 20 when the guard plate is shifted to theposition shown in Fig. 4, permitting insertion of the crank and cuttingoif the power. The plunger 21 posi tively locks the guard plate 10against move ment, and can not be released, until some authorized personunlocks and raises the cover 9, whereupon the plunger 21 may be presseddown to release the latch plate, by a suitable pin or other toolinserted through the small bore 20 aligned with'the hole 20.

From the foregoing, it will beapparent that this invention safe guardsmanual manipulation of power operated switch machines 1n a way tominimize the chances of lmproper operation of the swltch machine bypower to derail atrain. For example, if the switch machine should getout of order, and

it is necessary to crank it by hand to permit trains to move, power iscut off from the switch machine and can not be restored except by anauthorized personcapable of assuming the necessary responsibility. Suchan arrangement is desirable, because in practice it is sometimesnecessary for someone to crank the switch machine who may not know justwhat to do under such circumstances, and ,may thoughtlessly ,put powerback on the switch machine. After cranking it over,

vwith the result that under certain combinathrough said opening andnormally-preventr 7 ing insertion of said crank into saidsocket,

a power circuit. controller opened by the,

movement of said guard plate to an actuated position to permit insertionof thecrank,'and a sprin engaged latch for locking said guard plate inits actuated position, said latchbeing 1 V accessible to disengage itonly by an authorized person having a key for the locked cover.

' v In testimony whereof I afix my" signature.

I WINTHROP K. HOWE.

tion of circumstances the switch may be thrown by power under a train."It is as.

sumed that the authorized maintainer, hav ing a key to unlock the cover,will not release the latch plunger 21.holding the guard plate 10 in theposition to cut off power, until conditions are safe and proper to doso.

One specificembodiment of the invention has been illustratedand'described in ccnnection with a switch machine of one particulartype; and it is evidentthat the specificconstructio'n'disclosed issusceptible of modifiher, and a spring actuated locking device. for

cation and adaptation without departing from the invention. V.

What I claim is 1. In a switch machine, means permitting handoperationof the switch machine and including a movable member, power controlcontacts operated by movement of said meniretaining said member in itsoperated-position, said locking means being contained-in a lockedcompartment and releasable only by an authorized person holding a key tosaid compartment.

2. In a power operated switch machine, a. power cut-off switch, amanually operablemember for operating the switch to cut 05 power, andlocked means accessible only to an authorized person for holding saidmemher in its actuated position to. cut 02d the power. I v

3. In a switchmachine of the character described, operating mechanismincluding a socket to receive a hand crank, a guard plate preventinginsertion of the hand crank into 'saidsocket until said plate is shiftedto an operatedposition, a circuit controller governingthe application ofpower ofthe switch machine, said circuit controller beingfc'onnectedtosaid guard plate and opened by its movement to its operate-d position,and a spring engaged latch for locking said guard plate in its operatedposition, said latch beingcontained in a locked compartment.

4. In a switch machine of the character described, mechanismincluding asocket to re ceive a hand crank, a locked cover for the switch "machinehaving opening "therein through which the hand 'crank'm'ay be insert edinto said socket, a guard plate accessible an r

